Biomedical subjects

K T Lee

Publications and source records attributed to K T Lee.

At least 37 records · Page 2Linked to original sources

PubMed2001

Constituents of the essential oil of the Cinnamomum cassia stem bark and the biological properties.

GC-MS analysis on the essential oil (CC-oil) of Cinnamomum cassia stem bark led to the identification of cinnamaldehyde (CNA, 1), 2-hydroxycinnamaldehyde (2-CNA), coumarin (2), and cinnamyl acetate. The major volatile flavor in CC-oil was found to be 2-CNA. Coumarin was first isolated from this plant by phytochemical isolation and spectroscopic analysis. CNA and CC-oil showed potent cytotoxicity, which was effectively prevented by N-acetyl-L-cysteine (NAC) treatment. Intraperitoneal administration with CNA considerably decreased malondialdehyde (MDA) formation and glutathione S-transferase activity in rats. These results suggest that CC-oil and CNA can regulate the triggering of hepatic drug-metabolizing enzymes by the formation of a glutathione-conjugate.

Aldehyde Reductase↗

PubMed2001

Toxicology of Kalopanax pictus extract and hematological effect of the isolated anti-rheumatoidal kalopanaxsaponin A on the Freunds complete adjuvant reagent-treated rat.

We have reported that kalopanaxsaponin A (KPS-A) isolated from Kalopanax pictus have anti-rheumatoidal activity in the rat treated with Freunds complete adjuvant (FCA) reagent. In addition, it has been also reported that KPS-A is a potent antioxidant in the rheumatoidal rat. This research was undertaken to examine whether the saponins of KPS-A and -I could adjust the abnormal lipid metabolisms and hematological changes in immunological diseases. KPS-A significantly inhibited the increases in both triglycerides and total proteins in addition to the decrease in total cholesterol induced by FCA reagent treatment. KPS-A treatment decreased the number of leucocytes elevated by FCA reagent treatment. Excess dose of the methanol extract produced no severe toxicity on the body weight, wet organ weights and hepatic functions. Since LD50 value of K. pictus methanol extract was shown to be 4,033 mg/kg, it could be estimated to be a safe agent for anti-rheumatoidal herbal medicines.

Animals↗

PubMed2001

Constituents and the antitumor principle of Allium victorialis var. platyphyllum.

To search for cytotoxic components from Allium victorialis, MTT assays on each extract and an isolated component, gitogenin 3-O-lycotetroside, were performed against cancer cell lines. Cytotoxicities of most extract were shown to be comparatively weak, though IC50 values of CHCl3 fraction was found to be <31.3-368.4 microg/ml. From the incubated methanol extract at 36 degrees C, eleven kinds of organosulfuric flavours were predictable by GC-MS performance. The most abundant peak was revealed to be 2-vinyl-4H-1,3-dithiin (1) by its mass spectrum. Further, this extract showed significant cytotoxicities toward cancer cell lies. Silica gel column chromatography of the n-butanol fraction led to the isolation of gitogenin 3-O-lycotetroside (3) along with astragalin (4) and kaempferol 3, 4'-di-O-beta-D-glucoside (5). This steroidal saponin exhibited significant cytotoxic activities (IC50, 6.51-36.5 microg/ml) over several cancer cell lines. When compound 3 was incubated for 24 h with human intestinal bacteria, a major metabolite was produced and then isolated by silica gel column chromatography. By examining parent- and prominent ion peak in FAB-MS spectrum of the metabolite, the structure was speculated not to be any of prosapogenins of 3, suggesting that spiroketal ring were labile to the bacterial reaction. These suggest that disulfides produced secondarily are the antitumor principles.

Allium↗

PubMed2001

Trace organic contaminants in sediment and water from Ulsan Bay and its vicinity, Korea.

Sediment and water samples collected from 32 locations in Ulsan Bay and adjacent inland areas were analyzed for polycyclic aromatic hydrocabons (PAHs), nonylphenol (NP), octylphenol (OP), bisphenol A (BPA), organochlorine (OC) pesticides (HCB, HCHs, CHLs, and DDTs), and polychlorinated biphenyls (PCBs) to characterize their spatial distribution and contamination status. PAHs were detected in nearly all sediment and water extracts from Ulsan Bay and its inland locations. The sedimentary PAH concentrations ranged from 17 to 3,100 ng/g on a dry weight basis (DW), which were predominated by two- and three-ring aromatic hydrocarbons in river and/or stream, and four- to six-ring compounds in Ulsan Bay sediment. Concentrations of PAHs in pore water samples were generally two or three orders magnitude less than those of corresponding sediment samples. Maximum concentrations of NP, OP, and BPA in sediments were 1,040, 120, and 54 ng/g DW, respectively. Concentrations of OP and BPA were, on average, 5- to 13-fold less than those of NP. PCB concentrations in sediment ranged from 1.4 to 77 ng/g DW, which were predominated by lower chlorinated congeners such as di- through pentachlorinated biphenyls. Among different OC pesticides analyzed, concentrations of DDTs were the greatest, ranging from 0.02 to 41.9 ng/g DW. NP concentrations were greater at inner locations proximal to municipal wastewater discharges into rivers and/or streams, whereas the concentrations of PCBs and PAHs were great near the sites of high industrial activities. Sediment-pore water partitioning coefficients correlated with those of reported Koc or Kow values for selected PAHs in Ulsan Bay, but these varied by an order of magnitude for stream and/or river sediments.

Chromatography, Gas↗

PubMed2001

In vitro bioassay determination of dioxin-like and estrogenic activity in sediment and water from Ulsan Bay and its vicinity, Korea.

Extracts of sediment and water samples collected from Ulsan Bay, Korea, were screened for their ability to induce dioxin-like and estrogenic gene expression in vitro. Each sample was tested as raw extract (RE) and fractionated extract (FE). Based on the initial screening of RE, 23 of 31 sediment samples showed significant dioxin-like activity in H4IIE-luc bioassay, whereas most sediment samples did not elicit estrogenic response in MVLN bioassay. Most of the activities associated with FE samples revealed that mid-polar (F2) and most polar (F3) fractions were responsible for the significant reporter gene expression in H4IIE-luc bioassay. The results suggest that complex interactions may have depressed the activities of the known arylhydrocarbon receptor (AhR) agonists present in F1 samples. The F2 samples were the most active fraction. All F2 samples except one induced significant dioxin-like activity, and over half of the F2 samples induced significant estrogenic activity. Ten of the F2 samples produced magnitudes of response in H4IIE-luc bioassay similar to those induced by a 2,3,7,8-tetrachlorodibenzo-p-dioxin standard. Sediment associated with F2 samples was estimated to contain 24.9-826 pg TCDD-EQ/g DW. Based on a qualitative mass balance analysis, polycyclic aromatic hydrocarbons (PAHs) appeared to account for both the estrogenic and dioxin-like responses observed. Over half of the F3 samples were either cytotoxic or caused morphological changes in both H4IIE-luc and MVLN cells. Known concentrations of alkylphenols and bisphenol A were not great enough to account for both the estrogenic response and cytotoxicity observed for F3 samples. Despite the apparent toxic or stressful effects, most of F3 samples induced significant dioxin-like activity in vitro, adding to a growing body of evidence that suggests the presence of unidentified, relatively polar, AhR agonists in sediment from some areas.

Animals↗

PubMed2001

Contamination of polychlorinated biphenyls (PCBs) in sediments from Kyeonggi Bay and nearby areas, Korea.

To elucidate the characteristic distribution and contamination of polychlorinated biphenyls (PCBs) in sediments, 63 sediments and five benthic organisms from Kyeonggi Bay, Namyang Bay and Lake Shihwa, West coast of Korea, were analysed. Characterization of PCBs distribution in sediments was conducted by correlation between PCBs concentrations and environmental parameters, comparison of contamination level and composition of PCBs homologs between Kanechlor mixture (KC-mix) and sediments. The residues of PCBs in sediments were correlated with total organic carbon (TOC) and particulate organic carbon (POC) contents, not with mud contents and grain size distributions. Elevated concentrations of T-PCBs were found in sediments from Incheon North Harbor (INH) in Kyeonggi Bay. T-PCBs concentrations were decreased with distance increase from inner site of INH. The residues of T-PCBs in sediments from Namyang Bay were either non-detectable or near to detection limit. The contamination by PCBs in sediments from Lake Shihwa was also low. The PCBs congener profiles in INH were similar to those of KC-mix, while those in less contaminated sites showed relatively high percentage of lower chlorinated biphenyls. Sites K18 (580 ng/g or 48 ug/g-OC dry wt) and K19 (330 ng/g or 38 ug/g-OC dry wt) within INH exceeded the sediment quality criteria (SQC) (16 micrograms/g-OC as a KC-mix) derived from equilibrium partitioning (EqP) approach.

Environmental Monitoring↗

PubMed2001

Inactivation of SSI-1, a JAK/STAT inhibitor, in human hepatocellular carcinomas, as revealed by two-dimensional electrophoresis.

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is one of the most common human cancers, and many efforts have been paid to discover aberrant expression control in HCC, however the specific molecular mechanisms involved in hepatocarcinogenesis remain to be determined. METHODS: To investigate genomic changes that occur in human primary hepatocellular carcinomas (HCC), we carried out restriction landmark genomic scanning. This two-dimensional electrophoretic system displays 2000-3000 NotI-landmark sites in a single gel. RESULTS: We detected one landmark spot that showed diminished signal intensities in a majority of the HCCs we examined. Cloning revealed that this spot represented a NotI-cluster sequence that was enriched with CpG dinucleotides in the promoter region of a gene encoding Janus kinase (JAK)-binding protein, SSI-1 (also known as JAB1 or SOCS-1). Expression of the SSI-1 gene was markedly reduced in half of eight HCCs analyzed. CONCLUSIONS: This protein regulates the Janus kinase signal transducers and activators of transcription signal transduction pathway, which transmits signals from cytokines to the intracellular apparatus. These data suggest that dysregulation of the pathway relate with progression of HCC.

Carcinoma, Hepatocellular↗

PubMed2001

Distribution of organochlorine pesticides in sediments from Kyeonggi Bay and nearby areas, Korea.

The residues of oragnochlorine pesticides (OCPs) in 62 sediments from Kyeonggi Bay and nearby areas in the west coast of Korea were determined. The concentrations of chlordanes (CHLs) and DDTs showed a distinctive gradient of contamination between inner and outer sites of Incheon North Harbor (INH), whereas hexachlorocyclohexanes (HCHs) were uniformly distributed at most sites studied. The distribution of CHLs and DDTs was strongly correlated with total organic carbon contents in sediments while HCH residue levels were independent. Relationship between contaminant's concentration and environmental factors was analyzed by principal component analysis. Distribution patterns of T-CHLs, T-DDTs, and TOC were similar while those of T-HCHs, mud content, and grain size were similar. The notable contamination by CHLs and DDTs was found in INH where these levels were one or two orders of magnitude higher than other sites. The dominant OCPs in sediments were beta-HCH among HCH compounds, trans-chlordane among CHL compounds, and p,p'-DDD among DDT compounds. The higher concentrations and compositional pattern of OCPs in INH sediments indicate that INH is in the vicinity of the source.

Carbon↗

PubMed2001

Altered mucin gene expression in stone-containing intrahepatic bile ducts and cholangiocarcinomas.

Neoplastic transformation of epithelial cells is commonly associated with alterations in the synthesis and structures of mucin. Mucin protein epitopes and mRNA levels were frequently altered in adenocarcinomas compared to corresponding normal tissues. Clinically, hepatolithiasis has been regarded as a risk factor for cholangiocarcinoma. The aims of this study were to determine the possible alteration of mucin gene expression in stone-containing intrahepatic bile ducts and cholangiocarcinomas and to try to predict whether or not hepatolithiasis has a predisposition to development of cholangiocarcinoma. In situ hybridization with DIG-tailed oligonucleotides was performed on sections of paraffin-embedded tissues of stone-containing intrahepatic bile ducts, cholangiocarcinomas, and normal controls to identify the expression of MUC2, MUC3, MUC4, MUC5B, and MUC5AC in nonneoplastic and neoplastic biliary epithelium. The findings showed that (1) while multiple diverse mucin genes were expressed in the biliary epithelium, MUC3 and MUC5B mRNA were the main mucin genes expressed in the biliary epithelium of stone-containing intrahepatic bile ducts and normal controls; (2) absent or decreased expression of MUC2, MUC3, and MUC5B of mRNA was found in cholangiocarcinomas in contrast to nonneoplastic biliary epithelium; and (3) increased expression of MUC4 and MU5AC of mRNA was found in cholangiocarcinomas and the biliary epithelium, especially for dysplastic cells of stone-containing intrahepatic bile ducts compared with normal controls. In this study, using in situ hybridization we demonstrated that neoplastic transformation of the biliary epithelium is accompained by alterations in mucin gene expression, the altered mucin gene expression in dysplastic cells of stone-containing intrahepatic bile ducts may reflect a higher potential for malignant transformation in these cells, and it could be a precursor of cholangiocarcinoma in the presence of hepatolithiasis.

Adult↗

PubMed2001

Kalopanaxsaponin A is a basic saponin structure for the anti-tumor activity of hederagenin monodesmosides.

Hederagenin, delta-hederin [hederagenin alpha-L-arabinoside], kalopanax-saponin A [hederagenin 3-O-alpha-L-rhamnosyl(1-->2)-alpha-L- arabinoside], kalopanaxsaponin I [hederagenin 3-O-beta-D-xylosyl(1-->3)-alpha-L- rhamnosyl(1-->2)-alpha-L-arabinoside], and sapindoside C [hederagenin 3-O-beta-D-glucosyl(1-->4)-beta-D-xylsyl (1-->3)-alpha-L-rhamnosyl(1-->2)-alpha-L-arabinoside] were isolated from stem bark of Kalopanax pictus Nakai (Araliaceae). Among glycosides of hederagenin, disaccharide (kalopanaxsaponin A, commonly also called alpha-hederin), trisaccharide (kalopanaxsaponin I), and tetrasaccharide (sapindoside C) showed significant cytotoxicity on several types of tumor cells, while hederagenin itself exhibited only weak cytotoxicity and its monosaccharide (delta-hederin) was non-cytotoxic. From these results, it suggests that the arabinosyl moiety at C-3 blocks the activity of hederagenin and the position of the second sugar for glycoside linkage is also important for cytotoxicity. In the in vivo experiments, kalopanaxsaponin A (15 mg/kg, i.p.) apparently increased the life span of mice bearing Colon 26 and 3LL Lewis lung carcinoma, as well as cisplatin (3 mg/kg, i.p.). These results indicated that kalopanaxsaponin A has potential anti-tumor applications.

Animals↗

PubMed2001

The clinical significance of common bile-duct dilatation in patients without biliary symptoms or causative lesions on ultrasonography.

BACKGROUND AND STUDY AIMS: Although abdominal ultrasonography (US) is a good initial screening method for detection of biliary tract disease, we sometimes encounter patients who only have findings of dilatation of the common bile duct (CBD) on US, without specific biliary symptoms or jaundice. This study aimed to evaluate the causes and clinical significance of dilatation of the CBD in patients without biliary symptoms, jaundice, or causative lesions at US. PATIENTS AND METHODS: A total of 77 patients who had no biliary symptoms and whose internal CBD diameter was more than 7 mm, without definite causative lesions on US, were enrolled. Of these, 49 underwent endoscopic retrograde cholangiopancreatography (ERCP) and 28 underwent follow-up US or computed tomography (CT) instead of ERCP. We excluded patients whose bilirubin level had increased beyond the upper normal level or who had previous history of upper abdominal surgery including cholecystectomy. RESULTS: The ERCP findings were as follows: no lesion in 20 patients (40.8%), juxtapapillary duodenal diverticulum (JDD) in 11 (22.5%), benign stricture in ten (20.4%), distal CBD mass in two (4.1%), choledochal cyst in two (4.1%), anomalous union of the pancreaticobiliary duct (AUPBD) in two (4.1%), and choledochal cyst with AUPBD in two (4.1%). There were no differences in age or in alkaline phosphatase or gamma-glutamyl transpeptidase (GGT) levels between the patients who had causative lesions revealed at ERCP and those who did not. Among the 28 patients who did not undergo ERCP, 12 had returned to normal and eight had no change in CBD diameter on follow-up US. Among eight patients who underwent CT, there were four with normal findings, one with JDD, and three with suspected choledochal cysts. CONCLUSIONS: We detected a significant number of causative biliary tract lesions in asymptomatic adults with dilatation of the CBD on routine abdominal US; no laboratory or demographic parameters were useful for discrimination. Further diagnostic study will be helpful for the early diagnosis of biliary tract disease in such patients.

Adult↗

PubMed2001

The analysis of resectability and survival in pancreatic cancer patients with vascular invasion.

One of the major limitations of curative resection in patients with pancreatic cancer is local tumor extension to the mesenteric vessels. Thus, the purposes of our study were to assess the clinical value of contrast-enhanced spiral computed tomography (CT) in predicting the resectability and survival of patients with pancreatic cancer with suspicious vascular invasion and to assess the influence of curative resection on the survival of these patients. We enrolled 40 patients with pancreatic cancer who were suspected of having an involvement of the adjacent large vessels and who subsequently underwent operation with curative intent in the study. Resectability and survival were correlated with CT findings such as segment length, degree of encasement, and type and number of vessels involved. The survival rate was compared between the curative and palliative resection groups, and survival rate was compared between the resected and unresected groups. Of the 40 patients with adenocarcinoma of the pancreas, 14 had curative resections and 26 had palliative resections. The probability of curative resection was higher in patients with segment lengths less than 2 cm, as compared with segment lengths more than 2 cm. However, there was no difference in survival between the two groups. There were no differences in resectability and survival according to the degree of encasement and type and number of vessels involved. There was no difference in survival between the curative and palliative resection groups. There was no difference in survival between the resected and unresected groups. A survival benefit was not achieved by curative resection in patients with pancreatic cancer with vascular invasion. Therefore, it would be better to avoid aggressive surgery in patients with pancreatic cancer with vascular invasion.

Humans↗

PubMed2001

Use of SF-36 and SF-12 health status measures: a quantitative comparison for groups versus individual patients.

BACKGROUND: The extent to which SF-12 scores reflect SF-36 scores has not been well studied. OBJECTIVES: One purpose was to compare the sensitivity to change of the SF-36 Physical Function sub-score, and the Physical Component Summary Scores (PCS) of the SF-36 and SF-12 on patients with low back pain (LBP). A second purpose was to determine if the SF-12 could serve as a surrogate measure for the SF-36 when making decisions about individual patients. SUBJECTS: The sample consisted of 101 consecutive patients. MEASURES: SF-36 questionnaires were completed by patients at both initial and discharge examinations. SF-12 scores were calculated from the completed SF-36 questionnaires. Therapists' judgments of whether patients were judged to have returned to premorbid function served as the construct for meaningful clinical change. ANALYSIS: Receiver Operating Characteristic (ROC) curve analysis and repeated measures MANCOVA were used to assess sensitivity to change. Linear regression and 95% prediction bands described the extent to which SF-12 scores predict individual SF-36 scores. RESULTS: No significant differences were found between the ROC curve areas for the Physical Function sub-scale, the PCS-36 and PCS-12. No significant differences were found for the comparison of change scores between PF-36, PCS-36 and PCS-12 scores. CONCLUSION: The findings suggest that Physical Function sub-scores, SF-36 and SF-12 PCS scores are equally sensitive to change. SF-12 PCS scores do not adequately predict SF-36 PCS scores for individual patients. The PCS-12 should probably not be used to make judgments about the health status of individual patients with LBP.

Activities of Daily Living↗

PubMed2001

Pyogenic liver abscess: an audit of 10 years' experience and analysis of risk factors.

BACKGROUND/AIMS: Despite continuous improvement in image modalities, availability of potent antibiotics and advancement in the knowledge and treatment of pyogenic liver abscess, mortality remains high. The high mortality rate has underlined the important role of prognostic factors and prompts a number of studies to identify the risk factors. The present study aims to audit our experience in managing patients with pyogenic hepatic abscess during the period of 1989-1999, and to document changes in etiology, bacteriology and outcome, and to identify any risk factor associated with mortality. METHODS: One hundred and thirty-three patients with pyogenic hepatic abscess were studied to determine the demographic characteristics, clinical features, laboratory, bacteriological findings, methods of treatment, final outcome and risk factor analysis. All patients were treated with parenteral antibiotics. One hundred and twelve patients were subjected to ultrasound-guided percutaneous aspiration of the abscess. A percutaneous drainage catheter was inserted after aspiration in all patients. Laparotomy was done in 21 patients. RESULTS: The overall hospital mortality rate was 6% (8/133). Biliary tract disease was the most frequently identified cause. Leukocytosis, hypoalbuminemia and hyperbilirubinemia were common laboratory findings. The most common microorganism cultured was Klebsiella pneumoniae. The most common concomitant disease was diabetes mellitus. On univariate analysis, large abscess, diabetes mellitus and sepsis were significantly associated with hospital mortality. On multivariate logistic regression analysis, the presence of sepsis (p = 0.0031) was found to be an independent risk factor. CONCLUSIONS: In addition to early diagnosis and prompt treatment, making every effort to treat patients with adverse prognostic factors and systemic complications, the hospital mortality rate will be decreased significantly.

Adult↗

PubMed2001

Measurement of first-ray mobility in normal vs. hallux valgus patients.

Hypermobility of the first ray is one causative factor in development of hallux valgus and an important factor in the treatment of hallux valgus, but measuring first-ray motion is difficult. There are two known ways of measuring first-ray motion. One is measuring the bony angle on the lateral foot X-ray using a modified Coleman block. The other is using devices. However, neither is suitable for clinical application. We introduce a simple, fast and easy way of measuring first-ray range of motion. Using this method, we compared the first-ray motion between a normal group and a hallux valgus group. Forty normal and 60 hallux valgus patients were included in the measurement. We measured the first-ray range of motion in the following way: with one hand we held the 2nd, 3rd, 4th, and 5th rays at the metatarsal head level with a simple right-angled indicator. With the other hand, we held the first ray at the metatarsal head level using a simple right-angled device, such as a scale. Keeping the other rays fixed, we moved the first ray up and down and recorded the average distance (d) 10 times to reduce intra-measurement differences. We also measured and recorded the first metatarsal length (L) on the anteroposterior foot X-ray film. Finally, we calculated the first-ray range of motion (alpha) using the above data. We also measured the hallux valgus angle and intermetatarsal angle in the hallux valgus patient group. With this method, the average first-ray motion was 10.3 degrees in the normal group and 12.9 degrees in the hallux valgus patient group. If we define 14 degrees, (that is, above the 95th percentile in the normal group) as having hypermobility, 38% of hallux valgus patients had first ray hypermobility. There was no correlation between first-ray hypermobility and either hallux valgus angle or intermetatarsal angle.

Adult↗

PubMed2001

Tectorigenin, an isoflavone of Pueraria thunbergiana Benth., induces differentiation and apoptosis in human promyelocytic leukemia HL-60 cells.

Cytotoxic effects of six isoflavonoids, tectorigenin, glycitein, tectoridin, glycitin, 6''-O-xylosyltectoridin, and 6''-O-xylosylglycitin isolated from the flower of Pueraria thunbergiana Benth. together with genistein, a known differentiation and apoptosis inducer, were examined. Among these isoflavonoids, tectorigenin and genistein exhibited cytotoxicity against various human cancer cells; glycitein showed only mild cytotoxicity. These results suggest that the isoflavone structure and 5-hydroxyl group are crucial for the cytotoxic properties and that glycosides are inactive. Moreover, tectorigenin induced differentiation of human promyelocytic leukemia HL-60 cells to granulocytes and monocytes/macrophages, and caused apoptotic changes of DNA in the cells, as did genistein. Tectorigenin also inhibited autophosphorylation of epidermal growth factor (EGF) receptor by EGF and decreased the expression of Bcl-2 protein, with less activity than genistein. From these results, tectorigenin may be a possible therapeutic agent for leukemia.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2001

Costunolide induces apoptosis by ROS-mediated mitochondrial permeability transition and cytochrome C release.

Costunolide is an active compound isolated from the root of Saussurea lappa Clarks, a Chinese medicinal herb, and is considered a therapeutic candidate for various types of cancers. Nevertheless, the pharmacological pathways of costunolide are still unknown. In this study, we investigate the effects of costunolide on the induction of apoptosis in HL-60 human leukemia cells and its putative pathways of action. Using apoptosis analysis, measurement of reactive oxygen species (ROS), and assessment of mitochondrial membrane potentials, we show that costunolide is a potent inducer of apoptosis, and facilitates its activity via ROS generation, thereby inducing mitochondrial permeability transition (MPT) and cytochrome c release to the cytosol. ROS production, mitochondrial alteration, and subsequent apoptotic cell death in costunolide-treated cells were blocked by the antioxidant N-acetylcystein (NAC). Cyclosporin A, a permeability transition inhibitor, also inhibited mitochondrial permeability transition and apoptosis. Our data indicate that costunolide induces the ROS-mediated mitochondrial permeability transition and resultant cytochrome c release. This is the first report on the mechanism of the anticancer effect of costunolide.

Animals↗

PubMed2001

Responses of transformed root culture of Atropa belladonna to salicylic acid stress.

The effect of salicylic acid (SA) on tropane alkaloid production and the responses to SA stress of transformed root cultures of Atropa belladonna (belladonna) were investigated. Treatment of A. belladonna transformed roots with 0.2 mM SA did not have any effect on tropane alkaloid production, but two compounds were produced in the medium. These were identified as the SA derivatives methylsalicylate and methyl-o-methoxybenzoate by high-resolution mass spectrometry and UV spectrometry. In contrast, treatment with 2 mM salicylic acid stimulated tropane alkaloid release from the transformed roots into the medium by up to 35% of the total alkaloids after 24 h, and the SA derivatives were not observed in the medium. These results revealed that transformed root of A. belladonna exhibits distinct by different responses to SA stress depending on the SA concentration.

Journal Article↗